In general the performance of thin film transistors is impeded by grain boundaries and crystal defects in the semiconductor material in which the current-switching region of the transistor is formed.
It is known to use metal catalysts to enhance grain size, but metals may contaminate the crystallized semiconductor material, damaging or ruining the device.
It would be advantageous to enhance grain size and reduce defects in polycrystalline semiconductor material in which the current-switching region of a thin film transistor is to be formed while preventing or limiting metal contamination.